The present disclosure relates to a power supply apparatus for Light Emitting Diode (LED), and more particularly, to a power supply apparatus for LED, which protects an LED from an overcurrent that is momentarily generated when the LED is connected to the power supply apparatus for LED.
In installing a lighting device, generally, the lighting device is installed in a state where an input power has been disconnected, and thereafter, the power is applied.
However, due to the working environment, a lighting device may be sometimes required to be installed while a power is being supplied continuously. In this case, a power supply apparatus for a lighting device operates in a no-load state.
FIG. 1 is a circuit diagram illustrating a related art power supply apparatus for LED.
As illustrated in FIG. 1, when a lighting device such as an LED 2 is mounted on a power supply apparatus 1 for LED, a high current rapidly flows in the LED 2 because energy stored in the power supply apparatus 1 for LED is momentarily applied to the LED 2 due to the low impedance of the LED 2. Particularly, as the number of LEDs 2 is reduced, a higher surge current flows in the LED 2.
Therefore, a current flowing in the LED 2 is rapidly increased and thus deviates from a normal range, thereby damaging the LED 2. Due to this, the service life of the LED 2 is shortened.
Moreover, when the current deviating from the normal range flows, the current does fatal damage to the power supply apparatus 1 for LED as well as the LED 2, thereby threatening a user's safety.